Abstract
Ninety-five taxa of heterotrophic protists (amoebae, flagellates and heliozoa) were encountered in wild material and cultures established from marine samples from Tvärminne Archipelago, Gulf of Finland. Most species are flagellates, drawn from the cercomonads, the chlorophyceans, the choanoflagellates, the coccolithophorids, the cryptophyceans, the euglenids, the kinetoplastids, the bicosoecids, the chrysophyceans, the pedinellids and a variety of taxa of uncertain affinities (Protista incertae sedis). New names are Abollifer prolabens gen.et sp.nov., Bicosoeca mignotii sp.nov., Leucocryptos remigera sp.nov., Ollicola vangoorii (Lohmann 1908) comb. nov., Protaspis simplex sp.nov., Kiitoksia ystava gen. et sp.nov., Quadricilia rotundata (Skuja 1948) comb.nov., Rhynchobodo taeniata (Skuja 1956) comb.nov.